1. Field
The present invention relates to semiconductor devices and a method of manufacturing the semiconductor devices, specifically relates to a technique to integrate a temperature detection device with the semiconductor device including a SJ structure.
2. Description of Related Art
In a structure such that a temperature detection device is disposed in the middle of a principal surface of a semiconductor device, and that the semiconductor device includes a superjunction (SJ) structure in which plural p- and n-type columns are located relatively side by side, the temperature detection device is provided to detect the temperature of the semiconductor device, electric field distributions and potential distributions in a diode merged in the temperature detection device sometimes influences the behaviors of the semiconductor device. Accordingly, the temperature detection device, which is referred to as “a temperature detection diode” hereinafter, changes the electric charge balances in the semiconductor devices, reducing the breakdown voltages of the semiconductor devices in some cases.
In order to reduce the imbalance of electric charges due to the temperature detection diode in the case of detecting the temperature of the semiconductor device, WO2013/015014 has proposed a technique to make a width of columns under the temperature detection area where the temperature detection diode is provided shorter than a width of columns under the active area around the temperature detection area.
However, with the technique disclosed in WO2013/015014, the potential distribution becomes uneven at the boundary between the temperature detection area and an active area, the active area includes a path through which the main current flows, ascribable to the structure implemented by the p- and n-type columns. The uneven potential distribution could reduce the breakdown voltages of the semiconductor devices.